Cooling device for combustion-engines.



No 848,886.- PATENTED APR. 2, 1907.

- O. E. DURYEA. COOLING DEVICE FOR COMBUSTION ENGINES.

APPLICATION FILED APR.9. 1903.

UNITED STATES PATENT OFF ICE.

COOLING DEVICE FOR COMBUSTION-ENGINES.

Specification of Letters Patent.

Patented April 2, 1907.

Application filed. April 9, 1903. Serial No. 151,807.

To all whom it III/(by concern:

Be it known that I, CHARLES E. DURYEA, a citizen of the United States, residing at Reading, in the county of Berks and State of Pennsylvania, have invented certain new and useful lmproventents in Cooling Devices for Combustion-Engines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to heat-engines in which the combustion or explosion takes place in the cylinder of the engine or to such engines as use gases of such high temperature that the engine parts immediately in contact therewith must be kept from becoming overheated and the invention consists in certain improvements set forth in the following specification and shown in the accompanying drawings, forming part thereof.

The objects of my invention are to secure a uniform and advantageous temperature and to prevent excessive temperatures, to maintain this desired temperature closely, while preventing the undesired excessive temperature by forced circulation of air without the aid of moving mechanical parts, and to prevent damage by overheating of any of the important parts of the engine, to secure light weight, economic construction, and other objects, as will hereafter appear. The means I use to accomplish these objects are shown in the accompanying drawings, of which- Figure 1 is an elevation, partly in section. Fig. 2 is a bottom plan, while Figs. 3 and 4 are details illustrating more fully the construction of the parts.

Similar letters refer to similar parts throughout the several views.

While my invention may be applied to heatengines of many descriptions and to single or multiple cylinders, I have shown in Fig. l a single cylinder 1 attached to crankcase 2 by screwing a threaded portion of the cylinder into a properly-threaded part of the crank-case, which supports it firmly all around, but permits ready removal therefrom and makes a light but strong attachment. The cylinder is provided with. a flange 1 that serves as a stop to fix its position and forms an abutment against which it may be screwed tightly. This flange serves a further purpose in that a jacket 3 is attached at one end by being clamped between the flange and the crank-case 2.

. In order that the cylinder may stop with the inlet and exhaust valves in proper posiset-screw bearing against the screw-threads at the joint in any well-known manner.

These gaskets being quite To secure perfect workmanship, with uni- I forinity of metal all around, the cylinder is preferably of cast metal machined inside and out and is provided at its head end with a groove 5, into which the corresponding end: of the sheet-metal jacket 3 is inserted and.

held by being calked tightly in place by forcing a soft-metal ring 5 into the groove, which binds the jacket in place andrenders the joint tight. This jacket may be made single and adapted to retain a cooling liquid between it and the cylinder, as is common practice; but in order that highertemperatures than are commonly used may be secured I prefer to fill the space between the cylinder-wall and this jacket with something having a high vaporizing-point, either in the nature of a heavy oil or preferably in the nature of an easily-melted metallic alloy, and:

provide this jacket with an opening 7 through which the filling material may be introduced. The preferred alloy is of low heat conductivity, as likewise are most oils and liquids, so that the cylinder-wall may be of high temperature, while the outer surface of the jacket 3 may not be within many degrees of this same temperature. difficult to make a separate jacket join closely to the metal of the cylinder, the use of this alley or liquid insures a uniform passage for the heat from the cylinder-walls to the cooling means, whether of liquid or other kind 105 provided on the outside of the jacket. This fact is particularly valuable in connection with the use of copper for radiation and iron for the construction of the cylinder, because the expansion of the copper tends to increase I 10 Since it is its size and destroy thatintimate contact necessary to perfect conduction. More particularly is this true with a construction wherein the radiating devices areIriVeted to and well-known manner." The difference in temperature between the cylinderswall and the wall of the vjacket 3prmits" a much higher cylinder-wall temperature than would be possible if the water. were directly in contact therewith, and bysuitable thickness of alloy inside the jacket 3 the temperature of the motor maybe regulated accordingly, for

since water boils away at a given-temperature and since the thickness of such alloy determines practically the difference in temperature between the cylinder-wall and the acket-wall it will be seen that the temperature of. the cylinderwallcannot rise much I however, many sen ines have faces of the jacket 8, the tank 9, and the pi};

above a given or predeterminedpoint. Since, 1 complies s1onas, for examp e, 1nautomob'1le'use'-and since a poor .mixture requires a high com-- pression or temperature to roduce'spontaneous ignition, it is preferre to use a-temperature of the cylinder-wall much higher than the boiling-point ofwater and smce metallic alloys are heavy and athing-bjqdy of melted metal or liquid is preferred toathick one I keep the jacket 3 as small'as-practi cable, thus dimmishing quantity andlwight of material between it and the cylinderwall and secure a higher temperature by the. use

of some other liquid than. waterinithe outer jacket. Whatever liquid is used,;the' heat eventually must pass into the atmos' here by radiation, and since hot surfaces wi radiate more rapidly than cooler ones I. prefert'o fill the jacket 8 with a liquid. having a high vap orizing-point, such as high-fire-test-mineral oil, and provide means for eXposingthe sur es and connections to the air as freely and ly as ossible. To secure this result,-I preferab y use a tubular tank 9, Figs. 1 and 2, in

which a body of the liquid is contained, with suitable piping to and from the jacket of the engine to permit a circulationf-of theliquid.

I further provide either or both jackets,when

both are used, with radiating-wings to con duct the heat outward from-the jackets and expose a large metal surface to the air. It

'is of course self-evident that this liquid may be circulated inside the jacket 3 as readily and conveniently as inside the jacket 8 but duce a current.

because of the advantages of high cylinder: 7 wall temperature the method shown is Ypreferred.

The projecting fins 10 are preferably made of some metal having high thermal conductivity, such as copper, securely fastened to' of riveting "them: thereto the method employed of using a jacket of sheet metal carrying the fins is preferred. Fins of other shape, such as flanges or rings, may be used, but the preferred method is as shown. The tank 9, Figs. 1 and 2, is of ordinary and well-known construction, exposing large radiating-surface. 1 i I v I preferably place the cylinder with its jacket and the tank 9 in such relation to each other that a natural'circulation, due to the expansioh of the liquid under the influence of I heat, may result and that a free passage ofair around the cylinder and through the tank, asindicated by arrows, Fig. 2, may likewise re-' sult. If a motor-vehicle motor is placed with the tank at its rear and surrounded more or less completely by a casing 11, a current of 'air inay be induced through this casing by its funnel-shaped mouthcatching'the air through which the vehicle passes and by the utilization of the-energy of the exhaust-gases to'in- I accomplish this utilization as follows: In Fig. l a pipe 12 is shown leadingfrom the exhaust-valve to a muffler '13, in which the gases are allowed to expand, thus silencing the noise caused by their sudden exit, From the muffler 13 a smaller pipe leads to an injector 14,-whijch in turn is.

provided with a number of still smaller pipes pointing away from jthe cylinder. These pipes are so located and the sheet-metal case 1 1- is so placed that the escaping-gases exioo pend their energy inducing a draft of air around the cylinder and ejecting the'sameout through the tubes of the tank 9. The fact that the exhaust-gases have been fully expanded robs'them of most of their heat, and the high temperature of the liquid in the jacket and tank causes a wide difference in temperature between the mingled air and gases and the metallic surfaces with which they'come in contact, so that radiation of heat is very rapid and the gases pass away much heated, which arrangement permits a small amount of radiating-surface to suflice for a cylinder of large power. As will be seen in Fig. 2, the shape of the case 11 is dethe inner walls of the piston.

signed to secure the most efficient induction and ejection of the cooling current of air. For the purpose of preventing excessive temperature in such important parts as the exaust-valve I pipe from the muffler one or more additional jets and permit the same to blow upon the parts supporting the exhaustvalve, as shown at 15, Fig. 1'a simple yet efficient means of cooling any desired portion.

Since the piston is exposed to intense heat and with little chance for radiation, I provide for cooling this by ribs or fins projecting inwardly from its walls. These are usually attached by making them of some metal having a higher expansion coeflicient than the metal of which the piston is made and by this expansion insuring a firm contact be tween the fin-ringl6 (see Figs. 1 and 2) and In some instances, as in the two-cycle type, the piston is'exposedto a fresh charge each revolution, and these fins become very effective without further mechanism, while in the four-cycle type the crankcase may be left open, and thus fresh air permitted to reach the piston.

To secure increased effectiveness in some forms, I prefer to run a small pipe 17 into the cranlccase in such a manneras to permit one or more jets of the exhaust-gases to blow into the piston, causing a current of air to circulate therein. (See Figs. 1 and 2.)

Since with a small radiating-surface a rapid transfer of heat is necessary and since with a liquid having a high boiling-point the variation in density would not be great, it may sometimes be necessary to assist thecireulation of the liquid from the tankto the jacket and return by some means. While of course pumps or similar mechanical methods may be used in connection with other parts of my invention, I prefer to take from the niufiier or the exhaust-pipe a small pipe-18, which will force into the circulating medium bubbles of gas that lessen its density and cause the mingled liquid and bubbles to move rapidly upward. and toward the tank, in which case I provide on the top of the tank (see Fig. 1) a trap 19 to separate the bubbles from the liquid and permit their escape into the atmosphere.

Since high temperatures are not conducive to freedom from friction between mechanical bearing-s11rfaces, provide the piston wristpin with antifricti m-l earing devices, such as rollers, (see Fig. 1,) and in this way render this hmring practicallyimmune from heat troubles.

Of course provided on the outer surface of thetank 9 and the com:eating-pipes, as well as on the outer surface of the jackets. The utilization of the exhaust-gases for the purpose of inducradiating fins or flanges may be.

avoids mechanical means, with their increased cost of construction, their liability-to wear, rattle, and give trouble, and similar disadvantages. I prefer the means shown for utilizing the energy of the exhaust-gases for cooling purposes y expanding them, separating them into small. streams, and utilizin the velocity of the streams in their expande and cooled condition to induce and eject a current of air.

The passage of the expanded ases into the open air through'small tubes adds greatly to the silencing effect and lessens the need for a large muflier, securing an additional advantage because of this fact. In some instances, particularly where the oil-containing tank 9 is left open at the top, and therefore free from pressure, as shown in Fig. 1, I prefer to use the tank 9 not only as the reservoir for the cooling-oil, but for the lubricating-oil, and in this case provide means for supplying this oil to the surface of the piston or to other points wherelubrication is needed, as is shown by the pipe 21, leading to the groove 20, (or some oil-distributing arrangement,) as shown in Fig. 1. The size of the pipe 21 may be such as to feed the proper quantity of oil when hot, depending upon the inability of the oil to escape when the piston is in motion and its stiffness when cold, and when the piston is at rest to prevent undue leakage, or any well-known adjustment may be provided for the purpose of regulating the flow of oil. It is quite evident, however, that means for shutting off the flow of oil through the pipe 21 maybe provided, necessary. This provision to utilize the cooling-oil for lubrication purposes insures the introduction of fresh oil at frequent intervals and prevents that deterioration or staleness which may be the re 'sult of long usage of the oil for cooling purposes without being hermetically sealed or being renewed. If sealed, so as to preventevaporation, deterioration is practically impossible and renewal therefore unnecessary;

but since lubrication must be provided no regular shapes of heavy and light masses of iron. This uniformity practically secures perfect cylindricity under varying tempera tures and. permits the piston-rings to remain in contact with the cylinder-wall and prevent the escape of gases irrespective of variation in temperatures, amost essential feature in h1ghtemperature engines. It will readily be seen that at low temperatures thick lubricating-oil'will prevent much escape of the gases, but at high temperatures a mg a current of air not only avcids'utilizing perfect contact at all parts of the cylimler the power of the motor for tlns'purpose, but i and packing-rings must be depended upon. r 0

IlO

Since the highest pressures come at the head of the cylinder, this construction permits the Walls to be made lighter at the opposite end,

thus saving some weight without interfering with the perfection of behavior of the cylinders. The cylinder as constructed is free from warpin because the masses of iron are even everywhere, but may or may not be even lon itudinallythat is to say, one end of the. oyIinder may be "either thicker or thinner than the other, but at any given point of its length the thickness is uniform in a plane at right angles to its axis. Corrugation is not advisable on the cylinder-walls, for the outer portions of the corrugations being colder than the inner portions remain smaller and compress the metal under them, causing a slight corrugation of the inner surface, and thus tending to destroy perfect compressions. Corrugati'on of the jacket does not produce any deleterious eiiect, but, on the other hand, permits elasticity in the jacket that takes up any expansion, due to the high-expansion coefiicient of the jacket material, as well as increasing the radiating-surface, (see 22, Fig, 1.) The method of attaching the jacket shown permits ready removal when the cylinder is removed, for in this event the clamped end is no longer held, and the opposite end may be withdrawn from the groove in which it extends. gasket used must be of such material that the pressure of the jacket upon it when clamped will form a tight joint. If the jacket is not to be removed, the 'asket may be of metal calked into place. @ince the expansion co efficient of the jacket is higher than that of the cylinder, the filling between the jacketand cylinder must be either a liquid or some thing that becomes liquid at working tem peratures, so that it may absolutely and positively fill the space, and thus at all times pro p erly transmit the heat.

The use of a rigid jacket and an alloy having much tendency to shrink or expand when cold would necessitate a vent, as shown in Fig. 1, although in many cases the elasticity of the jacket will be ample to provide for this shrinkage or expansion without the use of a vent. Since there is need formore cooling effect around the combustionchamber than at the opposite end of the cylinder, I prefer to provide a moreeflicient cooling means and have thereforeshown the second jacket not extending the full length of the cylinder, utilizing air radiation as the second-means at the cooler end of the cylinder. This is but one ofthe many ways inwhich the temperature of the opposite ends of the cylinders can be regulated substantially at will. This etiect is accomplished, as shown, by air radiation only at one end and aliquid circulation with radiating-fins for'air-coolingoutside at the other.

Since the end of the connecting-rod formsaasse If removability is desired, theing the wrist-pin bearingis quite large, it is necessary to either keep the radiating-fins inside the piston short enough to permit this end free passage, or else, as I prefer, to make the radiating-surface on a separate remov- 7o able piece, as shown in Figs. 1 and 2.

I have shown an ordinary tubular tank; but this is not a necessary part of my invention, and any system of pipes adapted to contain more or less liquid and expose it to 7 5 the current of air will serve my purpose. It is quite common to equip pipes with radiating disks, as indicated in Fig. i, and this method I can utilize instead of the'tank or in conjunction therewith, if desired.

While it is ordinarily objectionable to sur-- round a motor with a casing, because it prevents accessibility to the working parts, I have overcome this objection by placing the valves, one of which, 24, is shown in Fig. 1, in 8 5 which view there is also shown an opening for the other valve and a central opering for the spark-plug, and ignition mechanism on the head of the cylinder, thus perfectly freeing the sides of the cylinder from all parts excepting the cooling devices. I construct, however, this casing detachable at the joints, which permits any side being removed or the entire casing being removed, if desired, being held in place by bolts 28, thus permitting 5 ready access to the cylinder for removing it or the jacket when needed. It will be noted that the casing has a vena contracta shape to form the injector, as shown.

I claim 1. In a heat-engine, a crank-case, a cylinder screwed thereinto, and a shcet-metal jacket removably attached at one end between said case and cylinder.

2. In a heat-engine one or more cylinders IO 5 having lateral flanges and removably attachcd'to a common crank-case by screwthreads in the ends of said cylinders and a sheet-metal jacket clamped at one end between said fianges and case, said cylinders rio being adapted to be stopped in apredetermined posit-ion by the interposition of suitable gaskets in conjunction with said flanges.

3. In a heat-engine a cylinderhavinga' sheet-metal jacket and adapted to be attached to a crank-case by the use of screw threads on the end of the cylinder and a flange which serve to both fix the cylinder and to clamp one end of the jacket.

4. In a heat-engine,.a crank-case, a cylin- 12o der screw ed thereinto -a sheet-metal jacket removably attached at one end betweensiiid case and cylinder, the cylinder at the other, end being provided with an exterior groove receiving the end of thejacket, and a soft- 12 5 metal ring in said groove inding said jacket in place.

5. In combination with a heat-engine whose piston is open to the air at one end, a

casing surrounding the same and having jets for causing a circulation of air through the same, said injector being connected with the muffler by said pipe, and a pipe leading; from an exhaust-passage into the open end of the piston to increase the circulation of air therein.

6. In a heat-engine, a piston open to the air at one end, a casing surrounding the engine and having openings to permit air circulationfa jacket surrounding the cylinder, a tank, means for the circulation of a cooling medium through said tank and jacket, a mufiier, an injector connected to the muffler and having multiple small outlet-jets for causing a circulation of air through the easing, and a pipe leading from the injector into the open end of the piston.

7. In a heat-engine, a piston open to the air'at one end, a casing surrounding the engine and having openings to permit air circulation, a jacket surrounding the cylinder, a tank, a trap at the top of the tank, means for the circulation of a cooling medium through said tank and jacket, a muffler, an injector connected to the mufller and having multiple small outlet-jets for causing a circulation of air through the casing, and a pipe leading from the injector into the open end of the piston.

8. In a heat-engine, a plurality of liquidcontaining jackets, a filling of easily-melted metallic alloy between one of said jackets and the cylinder, and piping for containing liquid, a circulating medium consisting of lubricating-oil and means for oiling the piston from the circulating-supply.

9. In combination with a heat-engine, a tank for containing oil, a casing inclosing the engine, a jacket for the cylinder, with means for causing a circulation of air through the casing, consisting of multiple jets of exhaustgases, means for forcing into said oil bubbles of gas to lessen the density of said oil, a connection between the tank and the cylinderjacket and a trap in the top of said tank to separate the bubles from the oil and to permit the escape thereof to the atmosphere.

10. The combination with a cylinder hav-' ing a flange, and a groove near one end, and a crank-case, of a jacket having one end seated in said groove and the other end engaged beneath said fiange, and gaskets interposed between the flange and the end of the crankcase and engaged by the end of said jacket as and for the purpose specified.

11. In a combination with a heat-engine, a

suitable jacket for containing oil, a supplytank connected therewith, a second jacket containing an easily-melted metallic alloy interposed between the cylinder-wall and said oil-jacket, means for forcing gas into the oil, and a separator in said tank constructed to eliminate the gases from the oil in said tank.

In testimony whereof I affix my signature in presence of two witnesses.

CHARLES E. DURYEA.

itnesses:

E. A. RUTH, H. D. HART. 

